Method for constructing couplings for rheostats and the like



A ril 19 -1927.

p 1 F. c. HERSEE METHOD FOR CONSTRUCTING COUPLINGS FOR RHEQSTATS AND THE LIKE Filed Mar h 10, 1925 Patented Apr. 19, 1927.

TENT lorries.

FREDERICK G. HERSEE, 0F WATERTON 1\T, MASSACHUSETTS.

METHOD FOR CONSTRUCTING COUPLINGS FOR RHEOSTATS AND THE LIKE.

Application filed March 10, 1923. Serial No. 624,215.

This invention relates to couplings or connectors for electrical apparatus and aims to provide novel and improved methods and structural means for establishing connection between a lead or conductor wire and a terminal head. The invention is particularly but not exclusively designed for use in respect to rheostats and other similar devices such, for example, as are employed in radio instruments where a series of contacts or terminals are usually arranged in a circular path for engagement successively by a swinging arm and in such close relationship that it is difficult to solder them securely in position without danger of causing short circuits between them.

Referring to the drawings:

Fig. 1 is a longitudinal section of a cap nut and coupling embodying the invention in one form thereof, a screw stud being shown in elevation engaged in such nut, and

Fig. 2 is a View partly in elevation and partly in section illustrating the manner of producing the cap nut and coupling of Figure 1.

In carrying out the invention in the form shown in Figure 1, I provide a base 10, which may be of hard rubber or the like and fix therein a series of threaded stems 11 each of which constitutes a master form or pattern for the cap nut to be produced, being for this purpose of the same dimension as the screw stems of the contact members with which the cap nuts are to be en gaged. These threaded stems have holes 12 extending a small distance in the outer ends thereof of a dimension to have the ends of the conductor wires 18, which are to extend from the cap nuts, fit snugly therein. The threaded stems 11 are then coated with plumbago or other suitable material adapted to prevent molecular union of an electrodeposit therewith. The projecting portions of the stems and the wires 13 for a substantial distance outward from the ends of the stems are then treated in an electroplating bath, and a deposit of copper or other suitable metal is formed upon the screw stems and upon the wires 13 leading outward therefrom.

This electrodeposit will unite molecularly with the wires 18, since they are not treated with the pumbago and thus a cap nut 14 is produced upon the threaded stem with a sleeve extenion 15 outward therefrom and firmly united with the wire. The cap nuts and the deposit 15 upon the wire may thus be built up to any desired thickness. Thus if the wires 13 before plating be approximately ten one-thousandths of an inch in diameter, the electrodeposit thereof would ordinarily be built up to a total diameter of twenty one-thousandths of an inch or more with a corresponding thickness of the walls of the nut 14. The nuts 14 with the wires 13 thus secured thereto may then be screwed 013 from the threaded stems 11 and are ready for use to be engaged with a threaded stem 11 of a rheostat or like contact.

I am aware that the invention may be 7 embodied in other specific forms without departing from the spirit or essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of constructing an electrical coupling comprising a lead wire and a cap nut molecularly united therewith, consisting of the provision of a master stem having an exteriorly threaded portion with a recess in one end thereof to receive a portion of the lead wire, the application of a protective coating to the exposed surface of the master stem for preventing molecular union of an electrodeposit therewith, and forming a cap nut by electro-deposit to en close the said threaded portion of the master stem and a portion of the lead wire, said cap nut and lead wire being thereby constituted a unitary assembly for detachable association with a support.

2. The method of constructing an elec-. trical coupling comprising a lead wire and a cap nut integrally associated therewith,

eons'niting oi the provision of a master stem having an exterioriy threaded portion, p051 tioning one end of a lead wire adjacentsaid threaded portion of the master stem, and 5 Running a cap nut by eieetro-deposit 0'1 metal enclosing and detachnbly engaging Said threaded portion of the master stein,

said cap nut having a sleeve extension 1301" tion snifnninding the lend wire for a sub stunt-in] distance and inoieunlzli'ly united 10 therewith.

In testimony \vhei'eot, l have signed my name to this speeiii fzlTiOIl.

FREDERICK C. HERSEE. 

